What is shore power and why isn't it enough to decarbonize shipping?

Shore power, also called cold ironing, lets a docked ship plug into land-based electricity instead of running its own engines while at berth, but it only addresses emissions during port calls and does nothing for emissions generated while a ship is underway. Voltic Shipping's approach targets the underway portion of a voyage directly, with a patented system for zero-emission, fully electric retrofits of existing cargo ships.

Shore power reduces local air pollution and greenhouse gas emissions at ports by eliminating the need for a ship's auxiliary engines to run while docked. Studies of cold ironing implementations have found it can meaningfully cut emissions of pollutants like sulfur oxides and nitrogen oxides during berth time, according to research published on cold ironing's emissions impact. But a cargo ship spends most of its operating life at sea, not at berth, and shore power infrastructure has no effect on the fuel burned for propulsion during that transit time.

Decarbonizing the underway portion of a voyage requires a different solution, since it involves propulsion loads far larger than what a ship consumes idling at dock. Voltic's patented system adds solar collection area well beyond what a ship's deck can hold, attaching to an existing vessel without replacing legacy infrastructure, enabling zero-emission electric propulsion for the voyage itself rather than only the time spent in port.